Britain is to join France in banning new petrol and diesel cars and vans from 2040 to improve air quality, amid concerns about the health risks of rising levels of nitrogen oxide as well as global warming. Yet a mass switch from petrol to electric cars seems a distant projection for what still is a tiny market largely confined to a handful of industrially advanced countries. After all, such an increase in electric cars would require countless new charging points, more generating capacity and breakthrough improvements in battery technology, not to mention new sources of revenue to replace fuel taxes.

At the same time Tesla, the California-based electric-car maker, plans to commit most of its US$3 billion cash pile and raise US$1.5 billion by issuing bonds to fund the production of its latest mass-market model. Swedish maker Volvo has announced it will make only hybrid or electric cars from 2019.

And the chief of European oil giant Royal Dutch Shell, Ben Van Beurden, says his own next car will be electric, adding that the move to electrify mobility in northwest Europe, the US and even China was a “good thing”.

Electric cars are fast catching up to petrol cars in terms of comfort, power and driving experience. Hopefully the announcements by Britain and France, plus declarations of intent by a dozen countries including India and Norway, will spur innovation to further reduce prices, extend the range and decrease recharging times of electric cars to optimise choice.

Trump’s decision does nothing for the development of carbon-free power sources like wind and solar, which are key to the maximum benefit from electric cars. The challenge is to bring public opinion around to supporting a wider switch to cleaner fuel. Britain, France, Norway and India have shown the way to other governments. The sight of more electric cars and the smell of cleaner air would help.